(1) Field of the Invention
The present invention relates to a remote maintenance system that makes an automatic failure diagnosis of electrical appliances for family use using a communication line, and transmits failure information to a service management center.
(2) Description of the Prior Art
A conventional remote maintenance system that detects malfunction of an electrical appliance located in each house quickly and correctly, and automatically reports it to a service center which provides maintenance services of the electrical appliance has been developed. In this type of remote maintenance system, a home server is located in each house under a maintenance contract of the electrical appliance with the service center, and the home server is connected to a center server which is located in the service center via a communication network. Each electrical appliance includes a monitor circuit for monitoring an internal state of itself, and reports the monitored internal state to the home server connected to the appliance via a LAN (Local Area Network) or the like. The home server sends the internal state reported by each electrical appliance to the center server via the communication line or the like. The center server holds per model of the appliance a failure decision model (hereinafter referred to as xe2x80x9ca failure modelxe2x80x9d) that is data indicating a reference value of normal operation in each part of the appliance, and decides whether the difference between each status value indicating the internal state of the applicable model received from the home server and the reference value indicated in the failure model is within a range of normal operation or not. As a result of the decision, when it is decided that there is a failure because the status value is beyond the normal range, the center server displays an instruction of dispatching a serviceman who is in charge of maintenance of the electrical appliance to the house which sent the status value.
As mentioned above, since the center server receives in advance the internal state of each part of each electrical appliance from the home server, it is possible to find easily a bad area of the appliance, and specify and prepare easily a replacement part, etc. for repair. As a result, a serviceman is not required for an advanced diagnosis, needs not carry unnecessary parts, and therefore can quickly repair the appliance.
However, there is a disadvantage that a load on the center server becomes heavy when the center server makes failure decisions of many kinds of electrical appliances located in each house in a centralized manner. On the other hand, if the home server of each house makes these failure decisions, the load on the center server can be reduced. In other words, if the home server of each house holds a failure model corresponding to all models of the electrical appliances located there, it can make this failure decision.
However, there is a problem in the conventional failure model, which is configured basically based on fixed reference values. That is, when the state of the appliance varies from the initial state due to secular changes or usage environment of each house, it becomes difficult for the home server to make an accurate failure decision, and it may decide that an apparatus has failed during normal operation or decide that the appliance is normal in spite of a failure, for example. Further, conventionally, when an electrical appliance goes wrong, the same information is displayed on both a display of a home server for a customer and a display of a center server for a serviceman. Although the information such as a part name inside the appliance, a name of a replacement part for repair, a product number code, a failure code, etc. is very useful for the serviceman who is going to repair the electrical appliance, display of such unfamiliar information is meaningless and inconvenient for the customer.
Accordingly, the object of the present invention is to provide a remote maintenance system that can make a failure diagnosis in touch with actual conditions such as usage environment of each electrical appliance by holding a latest failure model in a home server all the time. Also, the second object of the present invention is to display failure information of the appliance in a manner corresponding to a viewer""s needs.
In order to achieve the above-mentioned object, the remote maintenance system according to the present invention includes a center server that is located in a service center for performing maintenance of an electrical appliance and a home server that is located in each house and monitors a status of an electrical appliance in a house, wherein the center server and the home server are connected via a communication line. The home server includes: a status value acquiring unit operable to acquire a status value of each electrical appliance; a failure model receiving unit operable to receive from the center server a failure model which is information defining a method for deriving a decision whether the electrical appliance has failed or not from the status value; and a failure deciding unit operable to decide whether the electrical appliance has failed or not based on the acquired status value and the received failure model using qualitative reasoning, and the center server includes a failure model updating unit operable to update the failure model and send the updated failure model to the home server.
As mentioned above, in the home server of the remote maintenance system of the present invention, the failure model receiving unit receives a failure model from the center server, and the failure deciding unit decides whether the electrical appliance has failed or not based on the status value acquired from each electrical appliance and the received failure model. Also, in the center server, the failure model updating unit updates the failure model and sends the updated failure model to the home server.
In other words, the home server in the remote maintenance system of the present invention decides whether an electrical appliance has failed or not using the latest failure model updated in the center server. As a result, there is an effect that the home server can make a failure diagnosis in touch with the actual conditions of each electrical appliance, such as secular changes and usage environments, because the center server updates the failure model based on the status information of the electrical appliance which has been collected from each house.
Also, in order to achieve the second object, the home server in the remote maintenance system, according to the present invention, further includes a customer display unit operable to display failure information of the electrical appliance, the failure deciding unit sends information specifying contents of a failure of the electrical appliance to the center server when the failure deciding unit decides that the electrical appliance has failed, and the center server further includes: a holding unit operable to hold different contents of failure information which are prepared beforehand for a customer and a serviceman separately corresponding to a failure which can occur per model of the electrical appliance; a failure information sending unit operable to receive information specifying contents of a failure of the electrical appliance, specify failure information for a customer among the information held in the holding unit, and send the specified failure information to the home server; and a serviceman display unit operable to receive information specifying contents of a failure of the electrical appliance, specify failure information for a serviceman among the information held in the holding unit, and display the specified failure information for a serviceman.
Therefore, according to the remote maintenance system of the present invention, different contents of failure information can be displayed on the customer display unit in the home server and the serviceman display unit in the center server. In other words, on the customer display unit, failure and repair information can be displayed in a plain expression for a customer instead of technical and detailed information about an electrical appliance and the repair which seems to be unnecessary to the customer. As a result, referring to the customer display unit can prevent a wrong action of the customer when he/she finds trouble with the electrical appliance. Further, since technical, on-target and more detailed repair information can be displayed on the serviceman display unit for a serviceman, there is an effect that he/she can take appropriate measures against a failure of the electrical appliance efficiently and quickly even without any special repair skill or experience.